It's a great time to be a 409 fan, better even than back when they were new. Building a W-motor, as the 348/409 engines have been called, has always been fairly expensive if you're trying to make power. You could use the affordable truck block, but it has some pretty serious limitations, while the more desirable car block commands big dollars. A few years ago, Edelbrock opened up things a little with the release of its aluminum 348/409 heads, taking the cost of the heads more or less out of the equation.

"The only thing the market needs is a block," 409 guru Lamar Walden told us last year. "They're just about dried up." Factory-backed by Chevrolet, Walden got one of the original '69 ZL1 Camaros to campaign in the infancy of Pro Stock and was the builder/driver of the Barry Setzer Pro Stock Vega in the '70s, but he's been a 409 guy since day one, campaigning a blown, injected, 409-powered, A/Gas '33 Willys in the early '60s. He's built his own billet 409 blocks and the world's fastest 409, and he developed his own aluminum Z11 heads and intake. When World Products decided to hit the nostalgia market with an aluminum 409 block, the company tapped Walden for the R&D work. "The original block has several shortcomings," Walden told us. Borrowing heavily from the architecture of the modern big-block Chevy when designing a new block to overcome those problems, Walden kept the distinctive pieces that make a 409 a 409, including the heads, deck angle, and water pump.

You don't usually think of an aluminum race block as the more affordable solution, but at press time, World Products' website was listing its Merlin 409 block for $5,549. Stiff, perhaps, but at that price you get a ready-to-run block. Depending on your starting point, machining and repairs can put a factory block there. The Merlin block comes standard with 4.375-inch bores, and when combined with a modest 4.250-inch stroker crank, it displaces a tick above 511 ci (rounded down to 509 for nostalgia's sake). The sleeves will handle 4.550 inches, and the bottom end will clear a 4.500-inch stroke with big Chevy rods for 585 ci. Walden is talking about raising the deck 0.400 inch so a 4.750-inch crank can be used with long rods for more than 609 ci. The big-inch motors will need the flow capability of Walden's Z11 heads to feed it.

"What's really good about the aluminum block is it'll let the restorers have the last of the iron blocks, and it'll let the hot rodders make more power, cheaper than they ever could before," Walden said.